I have a split form. The datasheet displays several records. There is one field that needs updating "FUNCTION_SELECT". Once the user updates this field. I want a button that will export only the update records.

I am not familiar with VBA. I hope it is possible to perform this action with a Macro; and a few conditons.

sherlc29:
We can’t' actually do the project for you nor could we even if we wanted to from the very general information you've provided.
The steps involved would be to have the on current event note the current record.
Then, potentially, the before and after update events would need to be called to determine if the change(s) were actually made.
Once all this is done, your button could be made available. Depending on a dozen different things would determine how the code would be written as you note Excel in your title, there will need to be a query written that handles part of this transaction.